1. Field of Invention
The present invention relates to a short detection circuit. More particularly, the present invention relates to a short detection circuit adapted in a backlight module.
2. Description of Related Art
Recently, white-light emitting diodes (WLEDs) are widely used as the backlight source in the LCD panel. In order to drive more WLEDs in the panel, the driver IC provides high voltage to supply the WLEDs. When some of the WLEDs are broken, a short condition will happen to generate an extreme high voltage in the short WLED circuit and further damage the driver IC if there is no detection and protection mechanism.
Besides, the value of the high voltage generated by the short condition depends on the number of the broken WLEDs. If the value is not high, i.e. there are not many broken WLEDs, the driver IC may not be damaged. Thus, in order to give an appropriate threshold value of the voltage of the short condition, a design of the short detection circuit that can adjust the threshold value to signal the different short condition is important.
Accordingly, what is needed is a short detection circuit to detect the short condition with an adjustable threshold value to overcome the above issues. The present invention addresses such a need.